Antidazzle lamp



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" gaze Patented Mar. 2 7, 1934 NETED ANTIDAZZLE LAMP Carl Ferdinand Otto Miiller, Karlsruhe, Baden, Germany Application January 21, 1933, Serial No. 652,79? In Germany January 28, 1932 l 1 Claim.

My invention relates to lamps in which the source of light, constituted for example by an electric incandescent lamp, has covering it a large reflector in the form of a shell consisting 5 wholly or mainly of opaque substance such as sheet metal or of opal glass or a substance with a similar feeble permeability to light, and has disposed around it one or two rather small annular reflectorsmade of translucent glass, said 10 reflectors being so arranged in and over one another that they are all completely lit up and do not permit of the escape of a single ray of light directly, all the rays escaping only after reflection or diffusion by one of the reflectors, that is to say the illumination is free from dazzle and yet eiiective.

In known lamps of this type the annular lower reflectors are supported bya three arm metal frame which is secured to a hood of sheet metal enclosing the lamp holder and adjustably secured to the lamp tube, while the shell-shape upper reflector is supported either (in the case of hanging lamps) directly by the said sheet metal hood, or (in the case of standardor reading lamps) likewise by the said frame. This has inter alia the following disadvantages:-The frame is rather expensive and throws shadows. The annular reflectors are liable to collect dust as is also the shell-shape reflector; this is a great disadvantage particularly in spinning mills and like factories as well as in hospitals, schools and the like, as in such places the lamps required are those which collect a minimum of dust; moreoverv the covering of the lower reflectors with dust reduces their penetrability or perviousness to light and makes it necessary to clean them regularly, but this is mostly not done at all or not done thoroughly in the case of lamps hung high up owing' to the liability of the reflectors breaking. The

ming the rays of light that fall directly downwards, and which is situated below the source of light and is likewise supported by the said frame,

also actsas a receptacle for catching dust and,

insects.

My invention avoids these disadvantages by providing a bell made of clear glass, and.therefore transparent, as support for the annular reflectors, said bell .forming with the shell-shape reflector a complete covering for the source of light and the annular reflectors. This means makes it possible to exchange the annular reflectors by ones of different shape of cross-section and of differentdegrees of perviousness to light and thus to alter the light distribution curve, for example so as to change a lamp having a vertical lighting efiect to one having a rather horizontal lighting efiect, without affecting. the efllciency and the freedom of dazzle of the lighting.

In the accompanying drawing which illustrates small translucent shell that is needed for dim by way of example two constructions of lamps embodying my invention, Figure 1 is a sectional side elevation of ahanging lamp, and Figure 2 is a sectional side elevation of a standard lamp.

As illustrated in Figures 1 and 2 the electric incandescent lamp a forming the sourceof light has disposed above it a large shell-shape re-. flector b, Fig. 1, or N, Fig. 2, is surrounded by two smaller diffusers c and din the form of cylindrical rings disposed below the reflector b or b and partly in, partly over one another. The reflector b or b may be made of opal glass or a substance with similar feeble permeability to light, and the difiusers c and d may be made of frosted or other translucent glass. The diffusers c and-d are supported by a bell e, Fig. l, or e Fig. 2, which is mainly of clear glass and frosted only at the bottom and which may have either the stepped form shown in Figure 1 or that shown in Figure 2. The lowermost diffuser 02 may support .a shell 1 of frosted glass (Figure 1).

In the hanging lamp according to Figure 1 the reflector b is secured by means of screws 0 to a sheet metal hood is applied above the lamp holder it upon the lamp tube 12 and capable of adjustment, and the bell e is suspended by means of a narrow metal ring Z and screws m to the reflector I), while in the standard lamp according to Figure 2 the reflector b is mounted with its edge upon that of the bell e and the latter is mounted with its base upon a like hood k and engages in this hood by a neck n.

What I claim as my invention and desire to secure by Letters Patent is:

In a lamp the combination of a source of light, a large shell-shape reflector adapted for diffused reflection and disposed above said source of light, a plurality of separate smaller cylindrical diffusers of translucent glass and different diameters disposedbelow and co-axially with said re- 100 flector and at different distances from the same and leaving largeannular spaces between each other and said source of light, the latter having its centre disposed approximately inthe centre of the base plane of said reflector'and near the 

